Technical Field
Embodiments of the subject matter disclosed herein relate to an engine cooling system.
Discussion of Art
To reduce overheating of an engine and related components, a cooling system may route coolant through a single cooling circuit that includes the engine, a coolant pump, a radiator, and additional heat exchangers. The cooling system may have two parallel return paths from the radiator and back to the pump: a radiator main return path and sub-cooled return path. The sub-cooled return path may include more heat exchangers than the radiator main return path, thereby increasing a resistance of the sub-cooled return path relative to a resistance of the radiator main return path. Additionally, one or more of the heat exchangers may be positioned a vertical distance above the coolant pump. The coolant pump may be driven by an engine crankshaft and as engine speed decreases, flow and pressure in the engine cooling system may decrease. As a result, less coolant flow may flow through the sub-cooled return line and the components of the sub-cooled return line may not be completely flooded with coolant. This may cause thermal gradients to form across the un-flooded heat exchangers, thereby resulting in component degradation and non-homogeneous temperatures in the cooling system.